AL211 Allayer Communications, AL211 Datasheet - Page 12

• Manufacturer Part Number: AL211
• Description: Fast Ethernet Fiber to TP Media Converter
• Manufacturer: Allayer Communications

Figure 1-6
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Transformer
In the event of a receive link-failure, the receiver will go into a link-down mode. The AL211 will
take the following actions:
The far-end primary transceiver is normally in a link-up state and a back-up transceiver in a link-fail
state. During receive link-failure, the local AL211 will enable data transmission of the backup
transceiver by asserting the Redun# signal. The backup AL211 will then start sending copies of the
transmit signal.
The primary far-end receiver that receives the RF signal will enter the link-fail state. The back-up
transceiver will exit the link-fail state upon receiving a signal from the local AL211 re-establishing
the link. When the primary link is repaired, Redun# will be de-asserted and the secondary link will
be turned off re-establishing the primary link. During normal operation, the backup channel will be
transmitting idle signals but not data. Therefore, the link integrity status of the back-up channel is
available through the LED indicator.
Twisted Pair
Redundant Link
2.9.1 Receive Link Fault
1. Start transmitting remote fault signal; and
2. Put the TPO+ and TPO- pins in high impedance; and
3. Assert Redun# signal.
Local Primary
Local Back Up
Redun#
AL211
AL211
FOoff
FOoff
Reference Only / Allayer Confidential
Back Up
Primary
Far End Primary
Far End Back Up
AL211
AL211
FOoff
Redun#
FOoff
Twisted Pair
Transformer
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